A thermal process to toughen the high carbon steel by providing more ductility is（）
A.Tempering
B.Spheroidizing
C.Case hardening
D.Annealing
正确答案：Spheroidizing
A thermal process to toughen the high carbon steel by providing more ductility is（）
A.Tempering
B.Spheroidizing
C.Case hardening
D.Annealing
正确答案：Spheroidizing